Motor driving device manufacturing method and motor driving device

ABSTRACT

A motor driving device manufacturing method for manufacturing a motor driving device including a motor case, a rotor, and a stator disposed concentrically with the rotor on the outer periphery of the rotor, includes a measuring step for measuring a position of the stator relative to an axial center of the rotor from an inner side of the stator using a measuring device inserted in the stator; an adjusting step for adjusting the position of the stator from the inner side of the stator based on a measurement result of the measuring step using an adjustment device inserted in the stator, wherein the measuring step and the adjusting step are executed in a rotor not-inserted state, in which the stator is housed in the motor case and the rotor is not inserted in the stator; a stator fixing step for fixing the stator in the motor case; and a rotor shaft-support step for inserting the rotor in the stator and shaft-supporting the rotor on the motor case.

INCORPORATION BY REFERENCE

The disclosure of Japanese Patent Application Nos. 2005-356441 filed onDec. 9, 2005, and 2005-356442 filed on Dec. 9, 2005, including thespecifications, drawings and abstracts are incorporated herein byreference in its entirety.

BACKGROUND

The present invention relates to a manufacturing method for a motordriving device and a motor driving device manufactured using thismanufacturing method.

Hybrid vehicles with an engine and a motor driving device as drivesources have gained attention with respect to fuel efficiency,environmental protection, and so on. In the hybrid vehicles, the motordriving device acts as a motor that obtains power from a battery inorder to generate a driving force, and transmits the driving force to arunning mechanism side, to thereby cause the vehicle to run on themotor. The motor driving device may also act as a generator that obtainsa driving force from the engine and uses this driving force to chargethe battery. The motor driving device also performs a so-calledregeneration operation in which the surplus inertial force of thevehicle is collected as power during braking. The motor driving devicemay also be used during engine start-up.

Accordingly, a rotor of the motor driving device provided in a hybridvehicle is drivingly connected to a speed change mechanism side and anengine side to enable transfer of the driving force.

The motor driving device includes a stator and the rotor housed insidethe stator, and the stator and rotor are supported from a motor caseside. The stator is fixedly supported, whereas the rotor is rotatablysupported from a shaft-support portion provided in the motor case. In ahybrid vehicle, the motor case is rarely provided separately, andtypically a part of a transmission case housing the speed changemechanism in its interior doubles as the motor case.

In the motor driving device, the gap and concentricity between thestator and rotor are extremely important elements for determining theperformance of the motor driving device, and are therefore managed andadjusted strictly.

Japanese Patent Application Publication No. JP-A-7-241050 discloses atechnique for performing this type of adjustment. This technique relatesto a gap adjustment device for an electric automobile motor that adjuststhe gap by providing adjusting bolts in an upright manner in a flywheelhousing (equivalent to the motor case described heretofore), and adjustsan outer peripheral location of a stator core. A stator in this exampleis comparatively thin. In other words, the stator thickness in thedirection of a rotary axis (which shares an axial center with thestator) of the rotor is comparatively small.

SUMMARY

However, in the adjustment method described in Japanese PatentApplication Publication No. JP-A-7-241050, components (the adjustingbolts) other than the essential components of the motor driving deviceare required. Moreover, bolt holes must be provided in the motor case,and therefore this adjustment method is not preferable.

Furthermore, in recent years it has become necessary to increase thethickness of the motor driving device in the axial direction of therotor in order to satisfy the performance requirements of a motordriving device for a hybrid vehicle. FIG. 1 is a pattern diagram showingthe schematic structure of a thick motor driving device constructed torespond to these requirements. The left side of the drawing correspondsto an engine room ER side in which an engine E is disposed, and theright side of the drawing corresponds to a speed change mechanismchamber TR side in which a speed change mechanism T is disposed.

A stator S includes a stator core SC and a stator coil SW positionedrelative to the stator core SC. As shown in FIG. 2, the stator core SCis constructed by laminating a large number of substantially annularsteel plates p, and is fixedly fastened to a motor case by fasteningbolts b1 that penetrate fixing portions that are provided at apredetermined phase in the circumferential direction of each steel platep, in the lamination direction. Further, caulking, a welding processing,or a similar process is implemented on the steel plates p constructingthe stator core SC at a predetermined phase in the circumferentialdirection so that relative movement between the steel plates p isrestricted to a certain extent.

The position of the stator core in the left-right direction of FIG. 1(equivalent to the axial direction of the rotor) is determined accordingto a seating surface provided on the motor case. The position thereof inthe up-down direction (equivalent to the radial direction of the rotor),on the other hand, is determined by tightening the aforementionedfastening bolts since the housing space on the motor case side has somecomparative leeway.

In the structure described above, when the stator thickness (thethickness in the axial direction of the rotor) is comparatively thin, asin the technique disclosed in Japanese Patent Application PublicationNo. JP-A-7-241050, no problems arise when the stator position relativeto the axial center of the rotor (the stator axial center position) ismaintained at roughly the same relative position. However, as therequirements of the motor increase and the thickness of the motordriving device increases, vibrations generated by the rotating motor(including unevenness in the rotation of the rotor) increases when aconventional management method is applied.

The present inventors discovered through investigation that the cause ofthis problem is deformation of the stator core generated when thefastening bolts are tightened. FIGS. 3A and 3B illustrate thisdeformation. The drawings show a state in which a laminated stator coreis disposed vertically, FIG. 3A illustrates a state in which thefastening bolts are not tightened, and FIG. 3B illustrates a state inwhich the fastening bolts are tightened. In FIG. 3B, when the fasteningbolts are tightened, relative movement occurs between the steel platesaccording to the individual characteristics of the stator core, and as aresult it becomes impossible to maintain the linearity of the axialcenter of the stator. In this state, a core axial center position in athickness direction intermediate position of the stator core deviatesfrom the axial center of the rotor, and an adjustment must be performed.

The present invention thus provides, among other things, a fixing methodfor fixing a stator in an appropriate position relative to the axialcenter of a rotor by adjusting the position of the stator relative tothe axial center of the rotor accurately and quickly.

According to an exemplary aspect of the invention, a motor drivingdevice manufacturing method for manufacturing a motor driving deviceincluding a motor case, a rotor, and a stator disposed concentricallywith the rotor on the outer periphery of the rotor, includes a measuringstep for measuring a position of the stator relative to an axial centerof the rotor from an inner side of the stator using a measuring deviceinserted in the stator; an adjusting step for adjusting the position ofthe stator from the inner side of the stator based on a measurementresult of the measuring step using an adjustment device inserted in thestator, wherein the measuring step and the adjusting step are executedin a rotor not-inserted state, in which the stator is housed in themotor case and the rotor is not inserted in the stator; a stator fixingstep for fixing the stator in the motor case; and a rotor shaft-supportstep for inserting the rotor in the stator and shaft-supporting therotor on the motor case.

According to an exemplary aspect of the invention, a motor drivingdevice manufacturing method for manufacturing a motor driving deviceincluding a motor case, a rotor, a stator disposed concentrically withthe rotor on the outer periphery of the rotor, and a fastening devicefor fastening the stator to the motor case, includes a measuring stepfor measuring a position of an inner diameter surface of the stator; anddetermining a position of the stator relative to an axial center of therotor from the measurement result, and at the same time, the stator isfastened by the fastening device, wherein based on the position of thestator measured in the measuring step, a fastening amount of thefastening device relative to the stator is adjusted.

BRIEF DESCRIPTION OF THE DRAWINGS

Various exemplary aspects of the invention will be described withreference to the drawings, wherein

FIG. 1 is a view showing the cross-sectional structure of a motordriving device chamber;

FIG. 2 is a view showing an attachment structure of various parts of themotor driving device.

FIG. 3A-3B are illustrative views showing deformation of a stator coreaccompanying fastening;

FIG. 4 is a vertical sectional view of a measurement adjustment devicein use;

FIG. 5 is a plan view of the measurement adjustment device in use;

FIG. 6 is a sectional view showing a cross-section of VI-VI in FIG. 4;

FIG. 7 is a perspective view of the measurement adjustment device;

FIG. 8 is an exploded view of the measurement adjustment device; FIG. 9is an illustrative view of a process for fixing a stator to atransmission case:

FIG. 10 is an illustrative view of a process for fixing the stator tothe transmission case:

FIG. 11 is an illustrative view of a process for fixing the stator tothe transmission case;

FIG. 12 is an illustrative view of a process for fixing the stator tothe transmission case; and

FIG. 13 is an illustrative view of a process for fixing the stator tothe transmission case.

DETAILED DESCRIPTION OF EMBODIMENTS

The structure around a motor driving device M that is subjected tostator position measurement/adjustment using a measurement adjustmentdevice 1 functioning as a stator position measuring device according tothe present invention, the structure of the measurement adjustmentdevice 1, and an operation for fixing a stator S using the device 1 willbe described below in sequence.

Structure Around Motor Driving Device

FIG. 1 is a view showing the cross-sectional structure around a motordriving device M that is housed in and attached to a transmission caseMC (an example of a motor case), while FIG. 2 is an exploded viewillustrating a support structure of a stator S and a support structureof a rotor R of the motor driving device M. In FIG. 1, the left side isthe location of an engine room ER in which an engine E is disposed, andthe right side is the location of a speed change mechanism chamber TR inwhich a speed change mechanism T is disposed. As described above, therotor R of the motor driving device M is structured to be capable ofbeing drivingly coupled to the engine E and the speed change mechanismT, and is capable of transferring a driving force to and from the engineE and speed change mechanism T, respectively.

As is evident from FIGS. 1 and 2, the motor driving device M includesthe stator S and the rotor R. When the rotor R is attached, the rotaryaxis of the rotor R matches the axis of the stator S, and the axialcenter position of the rotor R is determined by a pair of shaft-supportbearings BRG (BRG1 and BRG2) supported by the transmission case MC.Hereafter, the center of the rotary axis of the rotor R, which isdetermined on the basis of the pair of shaft-support bearings BRG, willbe referred to as the axial center. The direction along the rotary axiswill be referred to simply as the axial direction (the directionindicated by D1 in FIG. 1), an orthogonal direction thereto will bereferred to as the radial direction (the direction indicated by D2 inFIG. 1), and the peripheral direction thereof will be referred to as thecircumferential direction (the direction indicated by D3 in FIG. 1).

The stator S includes a stator core SC and a stator coil SW positionedrelative to the stator core SC. The stator core SC is constructed bylaminating a large number of substantially annular steel plates p, asshown in FIG. 2. The lamination direction matches the axial directionD1. Each steel plate p employs a structure in which relative movementbetween the steel plates p is restricted by applying caulking or weldingprocessing at a predetermined phase in the circumferential direction.Further, each steel plate p is provided with protruding portions p1protruding in the radial direction in three locations at equal intervalsin the circumferential direction, and a bolt insertion hole p2 forfixedly fastening the stator core SC to the transmission case MC isprovided in each protruding portion p1. The laminated structure statorcore SC is fixedly fastened to a seating surface MC1 provided in thetransmission case MC by fastening bolts b1 serving as an example of afastening device or means.

Teeth t protruding radially inward in comb form are provided on theinner diameter side of each steel plate p. The stator coil SW is coiledvia cavity portions between each tooth t. Inner diameter side endsurfaces t1 of the respective teeth t form an end surface extending inthe circumferential direction.

The stator coil SW is impregnated with varnish and fixed in an insulatedstate. The spaces between the steel plates p are also impregnated withvarnish such that the steel plates p are fixed in a state wherebyinfiltration of water or the like is prevented. Further, by performingthis varnish impregnation, improvements in thermal conductivity and heatradiation are achieved.

The positioning of the stator S in the transmission case MC will now bedescribed. The positioning in the axial direction D1 is determined bycontact between the end surface of the stator core SC, shown on theright side of FIG. 1 (mainly the end surface of the protruding portionsp1), and the seating surface MC1 provided in the transmission case MC. Astator housing space formed in the transmission case MC is formed with apredetermined leeway in the radial direction D2 (the up-down directionin FIG. 1) such that the stator S possesses a predetermined loosenesswhen not fastened to the transmission case MC using the fastening boltsb1. Accordingly, the axial center position of the stator S in the radialdirection D2 of the transmission case MC is determined after thefastening bolts b1 are tightened.

The phase of the stator S relative to the transmission case MC in thecircumferential direction D3 is determined on the basis of the phaseposition in the circumferential direction D3 of the seating surface MC1provided on the transmission case MC relative to the aforementionedprotruding portions p1, and is set in accordance with the operation toinsert the stator S into the transmission case MC and the fasteningoperation performed by the fastening bolts b1.

The rotor R includes by a rotor main body RB provided on the peripheryof a rotor shaft RA, and the rotor shaft RA is shaft-supported from botha shaft-support bearing BRG1 provided on the engine room ER side and ashaft-support bearing BRG2 provided on the speed change mechanismchamber TR side.

As is evident from FIGS. 1 and 2, a motor driving device chamber MR isformed as an independent compartment between the engine room ER and thespeed change mechanism chamber TR. In the example shown in the drawings,a partition wall W formed integrally with the transmission case MC isprovided between the motor driving device chamber MR and the speedchange mechanism chamber TR, and one of the shaft-support bearings BRG2for supporting the rotor R is provided on the wall W.

Meanwhile, a partition cover C attached fixedly to the transmission caseMC is provided between the motor driving device chamber MR and theengine room ER. The partition cover C covers an end surface opening MCOof the transmission case MC from the left side of FIG. 1, therebydefining the motor driving device chamber MR. As is evident from FIGS. 1and 2, the position of the partition cover C in the radial direction D2and circumferential direction D3 is determined by a plurality of knockpins np provided in the end surface opening MCO. The other shaft-supportbearing BRG1 for supporting the rotor R is provided on the partitioncover C.

As is clear from the structure described above, the rotor R of the motordriving device M is supported rotatably by the shaft-support bearingBRG2 provided on the partition wall W and the shaft-support bearing BRG1provided on the partition cover C. In the present application, a rotorshaft-support portion RAS of the former will be referred to as a caseside shaft-support portion RAS2 (an example of a second shaft-supportportion), and a rotor shaft-support portion RAS of the latter will bereferred to as a cover side shaft-support portion RAS1 (an example of afirst shaft-support portion).

Stator Position Measurement Adjustment Device

FIGS. 4 to 8 show the structure of the measurement adjustment device 1.

FIG. 4 is a sectional view showing the main parts of the structure ofthe measurement adjustment device 1, and illustrates a condition inwhich the stator S is inserted in the transmission case MC, and themeasurement adjustment device 1 is disposed so as to be capable ofmeasuring and adjusting the position of the stator S. FIG. 5 is a planview corresponding to FIG. 4, FIG. 6 is a VI-VI sectional view of FIG.4, FIG. 7 is a view showing the measurement adjustment device 1 alone,and FIG. 8 is an exploded view thereof.

The measurement adjustment device 1 is structured to measure theposition of the stator S (the position of the stator S in the radialdirection D2) in a rotor not-inserted state, in which the stator S ishoused in the transmission case MC, the stator S is supported in theaxial direction D1 of the rotor R, and the rotor R is not inserted inthe stator S. Further, the measurement adjustment device 1 is structuredto be capable of adjusting the position of the stator S (the position ofan axial center Ss of the stator S relative to an axial center Rs of therotor R when the rotor R is supported on the transmission case MC) onthe basis of the measurement result. The measurement adjustment device 1is also structured such that the axis thereof (indicated by Z in FIG. 4)is determined from both the case side shaft-support portion RAS2 and thecover side shaft-support portion RAS1.

As is evident from FIGS. 4, 6, 7, and 8, the measurement adjustmentdevice 1 is structured such that end surface plates 2 forming anupper/lower pair in FIG. 4 are fixedly connected by sensor bars 3provided in four locations in the circumferential direction D3. Fourstator position adjustment mechanisms 4 are disposed so as to extendbetween the upper/lower pair of end surface plates 2 at equal intervalsbetween the respective sensor bars 3. The stator position adjustmentmechanisms 4 each include an eccentric cam 6 on a camshaft 5 disposed inthe axial direction D1.

Of the upper and lower end surface plates 2, an end surface plate 2 dpositioned on the lower side is a substantially ring-shaped annular endsurface plate 2 d, and the four sensor bars 3 are connected fixedly inlocations near the outer periphery of one end surface thereof. Each ofthe sensor bars 3 is positioned strictly on the annular end surfaceplate 2 d using a pair of pins 7. A guide shaft 8 is fixed to the centerof the opposite end surface to the end surface to which the sensor bars3 are fixedly connected.

As shown in FIG. 4, the guide shaft 8 includes on an upper end sidethereof a connecting portion 8 a connected to the annular end surfaceplate 2 d, and a fitting portion 8 b on an outer peripheral locationthereof, which is fitted into the shaft-support bearing BRG2 includingthe aforementioned case side shaft-support portion RAS2. Meanwhile, afirst center shaft insertion hole 8 c, into which a first center shaft 9a is inserted, is provided in the center of a lower end side. The firstcenter shaft 9 a is a guide member provided on an operation device 10used during an operation to fix the stator S to the transmission caseMC, and is provided so as to be capable of moving along an axis Z shownin FIG. 4, i.e. the axial direction D1, from a starting point determinedon an orthogonal plane to the axis Z. In the fixing operation, the firstcenter shaft 9 a and a second center shaft 9 b to be described below aredisposed in positions on a rotary axis Zr of the rotor R, which servesas a hypothetical reference during the operation.

Connection support portions including support bearings 11 for supportingthe camshaft 5 rotatably are provided on the annular end surface plate 2d in four evenly-spaced locations in the circumferential direction D3.Bearings which are capable of receiving thrust in order to receive aload from the camshaft 5 in the axial direction D1 are used as thesupport bearings 11.

Of the upper and lower end surface plates 2, an end surface plate 2 upositioned on the upper side including a quadrate plate 12 having asubstantially square or rectangle shape, and a connecting plate 13having a substantially annular shape, as seen from the plan view in FIG.5. The quadrate plate 12 and connecting plate 13 are structuredintegrally by bolt connections.

The other ends of the aforementioned four sensor bars 3 are connectedfixedly to locations near the outer periphery of the connecting plate13. Likewise in these connecting positions, each of the sensor bars 3 ispositioned strictly using the pair of pins 7. The quadrate plate 12 ispositioned on the opposite end surface to the end surface to which thesensor bars 3 are fixedly connected. As shown in FIG. 4, a conveyancehandle 14 is fixed to the quadrate plate 12.

The conveyance handle 14 is connected by bolts to the quadrate plate 12at the opposite end surface to the sensor bars 3, and a center shaftthrough hole 14 a for inserting the second center shaft 9 b is providedin an inner diameter location thereof. The second center shaft 9 b isused to convey the measurement adjustment device 1, and is also usedtogether with the first center shaft 9 a for reference positioningduring the fixing operation.

Connection support portions 15 for supporting the camshaft 5 rotatablyare provided on the connecting plate 13 in four evenly-spaced locationsin the circumferential direction D3. Each connection support portion 15includes a pair of radial bearings 16 for ensuring that the camshaft 5is centered favorably in the axial direction D1, and a stud bolt 17 forhalting rotation of the camshaft 5 appropriately.

A pin engagement member 18 for positioning the quadrate plate 12 isconnected to the quadrate plate 12 in the vicinity of each end in thelengthwise direction thereof using the knock pins np provided in the endportion opening MCO of the transmission case MC. As is evident from FIG.5, the pin engagement members 18 are fixed to each end of the quadrateplate 12 in the lengthwise direction by a pair of bolts 19, and each pinengagement member 18 includes a positioning hole 18 a for inserting theknock pin np. As shown in FIG. 4, when the knock pin np is inserted intothe positioning hole 18 a, the pin engagement member 18 is placed on theend surface of the end portion opening MCO in the transmission case MC.

In the measurement adjustment device 1, by inserting the guide shaft 8into the shaft-support bearing BRG2 provided in the case sideshaft-support portion RAS2 and inserting the knock pin np into thepositioning hole 18 a in the pin engagement member 18 provided at thelengthwise direction ends of the quadrate plate 12, the device 1 can bepositioned in the axial direction D1, radial direction D2, andcircumferential direction D3 relative to the transmission case MC.

More specifically, the device 1 is positioned in the radial direction D2by the case side shaft-support portion RAS2, and positioned in the axialdirection D1 and circumferential direction D3 by the knock pin np andpositioning hole 18 a.

Further, the relative position between the measurement adjustment device1, which is positioned in the transmission case MC by the knock pin npand positioning hole 18 a, and the stator S, which is fastened and fixedto the transmission case MC by the fastening bolts b1, is determined inthe circumferential direction D3 by the relative position of the knockpin np and positioning hole 18 a relative to the fastening bolts b1. Asshown in FIG. 6, the relative position thereof in the circumferentialdirection D3 is also set such that a sensor tip end 20 a of adisplacement sensor 20 supported on the device 1 and the inner diameterside end surface t1 of the teeth t provided on the stator S are disposedso as to face each other with the respective centers thereofsubstantially matching. Thus, the gap between the sensor tip end 20 aand the inner diameter side end surface t1 can be measured accurately bythe displacement sensor 20.

Note that other devices and means, such as a bolt and bolt hole, may beused as a positioning device or means for positioning the device 1 inthe transmission case MC instead of the knock pin np and the positioninghole 18 a.

Measurement and adjustment of stator position

The constitution by which the stator is positioned relative to themeasurement adjustment device 1 was described above. Next, measurementand adjustment of the position of the stator S will be described.

As shown in FIGS. 4, 6, 7, and 8, the displacement sensor 20 issupported by the sensor bars 3 serving as supports so as to be capableof measuring the position of the inner diameter surface of the statorcore SC of the stator S relative to the axial center of the rotor R.More specifically, five displacement sensors 20 are provided on each ofthe sensor bars 3 disposed in four evenly-spaced locations in thecircumferential direction D3.

Eddy current displacement sensors that detect the distance to aconductor according to a variation in an eddy current inside theconductor produced by electromagnetic induction are employed as thedisplacement sensors 20. The five displacement sensors 20 are disposedappropriately relative to the width of the stator core SC shown in FIG.4 in the axial direction D1 in five substantially evenly-spacedlocations, including the vicinity of the two ends of the stator core SC,so as to be capable of measuring the gap between the sensor tip ends 20a and the inner diameter side end surface t1, or in other words the tipend surface of the teeth t. Thus, the position of the stator S relativeto the axial center of the rotor R in the axial direction D1 can belearned. The displacement sensors 20 are an example of a measuringdevice or means.

Hence, using the five displacement sensors 20 disposed on each sensorbar 3, the position of the stator S in various locations along the axialdirection D1 can be learned.

Further, since the displacement sensor 20 is a non-contact typedisplacement sensor, such as the aforementioned eddy currentdisplacement sensor, which is selectively sensitive to a magnetic bodyor a conductor, it is capable of measuring the position of the innerdiameter side end surface t1 of the stator core SC accurately withoutbeing affected by substances interposed between the displacement sensor20 and stator core SC other than the magnetic body or conductor, inparticular the varnish that is adhered to the radial surface of thestator core SC.

Meanwhile, as described above, the sensor bars 3 are provided in fourevenly-spaced locations in the circumferential direction D3, andtherefore the position of the stator S in various locations along thecircumferential direction D3 can also be learned, and moreover, thecircle center position of the stator S can be learned from the output ofthe displacement sensors 20 disposed in four locations in thecircumferential direction D3. Then, by taking an average value of thecircle center position of the stator S in each position in the axialdirection D1, the position of the axial center (the average axial centerSs shown in FIG. 3B) of the stator S can be learned.

Hence, in the measurement adjustment device 1 according to the presentapplication, the pair of end surface plates 2 connected by the sensorbars 3, the members belonging to the end surface plates 2, and thedisplacement sensors 20 are examples of the measuring device or means.Further, the mechanism for positioning and supporting the displacementsensors 20 relative to the rotor shaft-support portions RAS, i.e. thepair of end surface plates 2, the sensor bars 3, the guide shaft 8, thepin engagement member 18, and so on, are examples of a support.

As a result, with the measurement adjustment device 1, the axis Z of themeasurement adjustment device 1 can be matched to the position of thehypothetical axis Zr of the rotor R, and therefore, as described above,the position of the stator S (the position of the stator core SC)relative to the axial center of the rotor R can be determined strictlyby obtaining the output of the displacement sensors 20.

As shown in FIGS. 4, 6, 7, and 8, the eccentric cam 6 is provided oneach of the camshafts 5 provided in four evenly-spaced locations in thecircumferential direction D3. As shown in FIG. 6, here the eccentric cam6 has a cam surface 6 s which is offset from an axial center 5 z of thecamshaft 5. Hence, the cam surface 6 s is capable of reaching a positionthat is removed from a position near the axial center 5 z of thecamshaft as the camshaft 5 rotates. As is evident from FIGS. 4 and 6,the cam surface 6 s is disposed so as to abut against the innerperipheral surface of the stator core SC near this removed position, andis therefore capable of moving the stator S in the radial direction D2by pushing the inner peripheral surface of the stator core SC (the innerdiameter side end surface t1 of the teeth t).

Adjustment in the radial direction D2 was described above, but in themeasurement adjustment device 1, unique measures are also taken withrespect to the disposal position of the cam 6.

As shown in FIGS. 4 and 7, the cam 6 is disposed in a positioncorresponding to the lower end portion of the stator core SC in theaxial direction D1. In this position, the stator core SC abuts againstthe seating surface MC1 when inserted into the transmission case MC. Inthis example, specifically, the cam 6 is disposed such that the lowerend surface (bottom surface) of the cam 6 is positioned in asubstantially identical plane to the seating surface MC1 of thetransmission case MC supporting the lower end surface of the stator coreSC (stator S).

As will be described below, adjustment of the stator position using themeasurement adjustment device 1 is performed in a vertical attitude withthe opening MCO of the transmission case MC open to the upper side. Inthis condition, the load of the stator S acts on the steel plate p ofthe stator core in the vicinity of the seating surface MC1, andtherefore it is most desirable to adjust the position of the steel platep in this location. According to a study conducted by the presentinventors, when the upper side location of the stator core SC in avertical direction (the axial direction D1) is pushed by the cam 6during adjustment while maintaining the vertical attitude, the entirestator S simply tilts relative to the axial direction D1 and the steelplate p contacting the seating surface MC1 cannot be moved easily. As aresult, the stator S may return to its original state followingadjustment by the eccentric cam 6 such that an adjustment failureoccurs.

Hence, in the measurement adjustment device 1, the cam position is setnear the lower end of the stator core SC, as described above, so thatthe position of the stator S in the radial direction D2 can be adjustedappropriately in various locations in the circumferential direction D3using the eccentric cams 6 disposed at equal intervals in thecircumferential direction D3.

In the measurement adjustment device 1 according to the presentapplication, the adjusting device and means includes the pair of endsurface plates 2 connected by the sensor bars 3, the members belongingto the end surface plates 2, and the stator position adjustmentmechanism 4. Furthermore, the stator position adjustment mechanism 4includes an adjustment tool serving as an example of the adjustingdevice and means, and the camshaft 5 includes a rotary shaft thereof.

Stator Position Adjustment

Next, a series of operations for measuring the position of the stator Susing the measurement adjustment device 1, performing an adjustment onthe basis of the measurement result, and fixing the stator S to thetransmission case MC will be described.

This series of operations includes (1) a vertical disposal process fordisposing the transmission case MC on the operation device 10 in avertical attitude, (2) an insertion process for inserting the stator Sinto the transmission case MC, (3) a temporary holding process fortemporarily holding the stator S in the transmission case MC, (4) adisposal process for disposing the measurement adjustment device 1 inthe stator S, (5) a measuring process for measuring the stator position,(6) a releasing process for releasing the temporary hold, (7) anadjustment amount derivation process for deriving an adjustment amountof the stator S on the basis of the measurement result, (8) anadjustment process for adjusting the stator position with no fasteningforce, (9) a fixing process for fastening and fixing the stator S to thetransmission case MC, and (10) a shaft-support process for removing themeasurement adjustment device 1 and attaching the rotor R.

These Processes Will Now be Described in Sequence.

1. Vertical Disposal Process

In this process, the transmission case MC is disposed on the operationdevice 10 in a vertical attitude. As shown in FIG. 9, the transmissioncase MC is disposed such that the end portion opening MCO of thetransmission case MC is on the upper side and the case sideshaft-support portion RAS2 provided on the transmission case MC is onthe lower side. Needless to say, the axis Z of the first and secondcenter shafts 9 a, 9 b provided on the operation device 10 matches thehypothetical axis Zr of the rotor R determined in the transmission caseMC. Here, the operation device 10 includes an attitude holding tool.

At this time, the shaft-support bearing BRG2 in the case sideshaft-support portion RAS2 is implanted in the transmission case MC, andthe knock pin np is inserted in a predetermined location in the endsurface opening MCO. Using these two members BRG2, np, the measurementadjustment device 1, and by extension the stator S, are positioned.

2. Insertion Process

As shown in FIG. 9, the stator S is inserted into the vertical attitudetransmission case MC. This insertion operation is performed by droppingthe stator S into the transmission case MC such that the stator S issupported on the seating surface MC1 provided in the transmission caseMC. Once insertion is complete, the up-down direction position (theaxial direction D1 position) of the stator S is fixed, and the relativephase (the circumferential direction D3 position) relationship betweenthe transmission case MC and stator S is also substantially fixed. Onthe other hand, as described heretofore, a slight looseness is permittedin the horizontal direction (the radial direction D2 position).

3. Temporary Holding Process

As shown in FIG. 9, the stator S is temporarily held within thetransmission case MC in a fastened state using the fastening bolts b1.The fastening force at this time is substantially identical to thefastening force generated when the stator S is fixed to the transmissioncase MC. When this fastening operation is performed, the stator core SCmay deform depending on the individual characteristics thereof, as shownin FIG. 3B.

4. Disposal Process

As shown in FIG. 10, the measurement adjustment device 1 is disposedinside the transmission case MC with the stator S in a fastened state.This disposal operation is performed using the second center shaft 9 bto insert the first center shaft 9 a into the guide shaft 8 while themeasurement adjustment device 1 is suspended by the conveyance portion14 a.

During the lowering operation, the fitting portion 8 b of the guideshaft 8 positioned on the lower side is guided and centered by theshaft-support bearing BRG2 in the case side shaft-support portion RAS2.Meanwhile, the pin engagement members 18 provided on the two endlocations of the quadrate plate 12 positioned on the upper side arepositioned by the knock pins np.

With this structure, the shaft-support bearing BRG2 exhibits a centeringfunction, and the knock pins np also exhibit a centering function.Moreover, the entire device 1 is supported from the lower side by theend surface opening MCO.

5. Measuring Process

As shown in FIG. 11, the position of the inner diameter side end surfacet1 of the teeth t provided on the stator core SC is measured using anoutput from the displacement sensors 20 while the measurement adjustmentdevice 1 is disposed in the transmission case MC.

The output of the displacement sensors 20 is gathered from eachdisplacement sensor 20 in a different position in the up-down direction,and the circle center position of the stator S in different up-downdirection positions (axial direction D1 positions) is determined as thestate of deformation of the inner diameter surface of the fastenedstator S by a computer (not shown) structured to determine the positionof the stator S on the basis of the output of the displacement sensors20. As a result, as shown in FIG. 3B, circle center positions at eachheight from the seating surface MC1 side through a representativeposition of the stator S to a location near the upper end are determinedindividually as coordinates on an orthogonal plane to the axialdirection D1. Here, the computer that performs this calculationprocessing is an example of a stator position deriving device and means.Note that the aforementioned representative position of the stator Sdenotes the position of the axial center of the stator S determined asan average value of the circle center positions of the stator S in eachposition in the axial direction D1.

Note that when the axial center positions of the rotor R and stator Smatch in this measuring process, the following adjustment process neednot be performed, and the motor driving device M can be completed byremoving the measurement adjustment device 1 from the transmission caseMC and attaching the rotor R.

6. Releasing Process

As shown in FIG. 12, the fastened state of the stator S is released byloosening the fastening bolts b1, whereby the stator S is set in an openstate with no fastening force applied thereto.

7. Adjustment Amount Derivation Process

As shown in FIG. 3D, the position of the stator S is adjusted such thatthe average axial center Ss, which is an average value of the circlecenter positions of the stator S at each height, is contained within apredetermined range relative to the hypothetically set axial center Rsof the rotor R with the stator S in a fastened state. Hence, the averagevalue of the circle center positions in each up-down direction position,determined by the aforementioned computer, is calculated, whereby theaverage axial center Ss of the stator S is determined. The correctcircle center position (Sb in FIG. 3D) of the lowermost portioncontacting the seating surface for containing the average axial centerSs within the target range is then determined as a target adjustmentposition. The position in which the lowermost portion circle centerposition Sb of the stator S contacts the seating surface MC1 of thetransmission case MC does not vary, irrespective of whether the stator Sis in the fastened state or the open state, and therefore the circlecenter position Sb of the lowermost portion is set as the targetadjustment position when the stator S is in an unfastened state. FIG. 3Cshows the relationship between the lowermost portion circle centerposition Sb and the axial center Rs of the rotor R. Note that the targetadjustment position is determined as the position of the stator when theaverage axial center Ss of the inner diameter surface of the stator Smatches the axial center Rs of the rotor R in the representativeposition of the stator S along the axial direction of the rotor R.

Note that the lowermost portion circle center position Sb set as thetarget adjustment position of the stator S may be derived on the basisof eccentricity information relating to the eccentricity of the axialcenter Ss of the fastened stator S to the axial center Rs of the rotorR.

More specifically, in the measuring process described above, theeccentricity direction and an eccentricity distance a of the axialcenter Ss of the stator S in the fastened state relative to the axialcenter Rs of the rotor R, as shown in FIG. 3B, is determined as theaforementioned eccentricity information. Then, using an axial center Ssoof the stator S prior to adjustment in the open state produced by thereleasing process described above as a reference, a position offset bythe eccentricity distance a (determined as the eccentric state describedabove, in an opposite direction to the eccentricity direction,determined as the eccentricity information described above) is derivedas the lowermost portion circle center position Sb serving as the targetadjustment position of the stator S. Hence, when the stator S having thecircle center position Sb derived in this manner as its lowermostportion position is in the fastened state, the axial center Ss thereofmatches the axial center Rs of the rotor R. In this case, an operationmay be performed to shift the stator S from its current position in theopposite direction to the eccentricity direction by the eccentricitydistance a.

Further, instead of the eccentricity information described above, thelowermost portion circle center position Sb set as the target adjustmentposition of the stator S may be derived on the basis of movementinformation relating to the movement of the axial center Ss of thestator S in the fastened state from the axial center Sso of the stator Sin the open state.

More specifically, after measuring the axial center Ss of the stator Sin the fastened state in the measuring process described above, as shownin FIG. 3B, the axial center Sso of the stator S prior to adjustment inthe open state produced by the releasing process described above ismeasured. A movement direction and a movement distance b of the axialcenter Ss of the stator S in the fastened state shown in FIG. 3Brelative to the axial center Sso of the stator S in the open state arethen determined as the movement information. Then, using the axialcenter Rs of the rotor R as a reference, a position offset by themovement distance b, determined as the movement state described above,in an opposite direction to the movement direction, determined as themovement information described above) is derived as the lowermostportion circle center position Sb serving as the target adjustmentposition of the stator S. Hence, when the stator S having the circlecenter position Sb derived in this manner as its lowermost portionposition is in the fastened state, the axial center Ss thereof matchesthe axial center Ss of the rotor R. Note that measurement of the axialcenter Sso of the stator S in the open state is performed aftermeasurement of the axial center Ss of the stator S in the fastenedstate, and therefore when the axial center Ss of the stator S in thefastened state already matches the axial center Rs of the rotor R,measurement of the axial center Sso of the stator S in the open statecan be omitted to reduce the operation duration. In this case, anoperation may be performed to shift the stator S in the oppositedirection to the movement direction by the movement distance b using theaxial center Rs of the rotor R as a reference.

8. Adjustment Process

As shown in FIG. 12, the stator S is moved and adjusted by operating thecamshaft 5 to rotate appropriately so that the lower portion position ofthe stator S is adjusted to the appropriate lowermost portion circlecenter position Sb determined in the manner described above. Thismovement and adjustment of the stator S is performed by operating thecamshaft 5 to rotate such that a part of the inner peripheral surface ofthe stator core SC in the circumferential direction D3 is pushedradially outward by the cam surface 6 s of the eccentric cam 6. At thistime, the eccentric cam 6 is disposed in a position corresponding to thelower end portion of the stator core SC, and therefore the lowermostportion circle center position of the stator S is moved and adjustedfavorably.

In so doing, the average axial center Ss of the representative positionof the stator S in the fastened state fastened by the fastening bolts b1is positioned within the allowable range.

9. Fixing Process

Once the adjustment process described above is complete, the stator S isfastened and fixed to the transmission case MC again using the fasteningbolts b1, as shown in FIG. 13. By performing the measuring process andadjustment process described above, centering can be performed with anextremely high degree of precision even in the motor driving device Musing the laminated stator core SC, which has a tendency to deform in afastened state. In the final state, as shown in FIG. 3D, the axialcenters of the rotor R and stator S match in the representative positionm.

10. Shaft-support Process

When the axial center Rs of the rotor R and the axial center Ss of thestator S match in this manner, the measurement adjustment device 1 isremoved from the transmission case MC, the rotor R is attached, and thusthe motor driving device M reaches completion.

Further, if the axial center Rs of the rotor R and the axial center Ssof the stator S can be confirmed to match in the measuring processdescribed above, the measurement adjustment device 1 may be removed fromthe transmission case MC and the rotor R may be attached such that themotor driving device M reaches completion.

Other Embodiments

(1) In the embodiment described above, the measurement adjustment deviceis centered using both the shaft-support bearing provided on the caseside shaft-support portion and the knock pins provided on the endportion opening. However, when an operation is performed in a verticalattitude with the measurement adjustment device supported in a verticaldirection, as in the embodiment described above, and an attempt is madeto align the axial center of the measurement adjustment device with theaxial center of the rotor, the radial direction position can besubstantially determined at either end of the up-down direction, andtherefore either one of the shaft-support bearing provided on the caseside shaft-support portion and the knock pins provided on the endportion opening may be used as a reference.

(2) Further, in a structure where the case side shaft-support portionand the cover side shaft-support portion are provided, as illustrated inthe embodiment described above, instead of providing the case sideshaft-support portion between the motor driving device chamber and thespeed change mechanism chamber and providing the cover sideshaft-support portion between the engine room and the motor drivingdevice chamber, the cover side shaft-support portion may be providedbetween the motor driving device chamber and the speed change mechanismchamber and the case side shaft-support portion may be provided betweenthe engine room and the motor driving device chamber.

In the examples described heretofore, one of the shaft-support portionsis provided on the case side, and the other shaft-support portion isprovided on the cover side. However, a pair of partition covers definingthe motor driving device chamber may be provided, and a pair ofshaft-support portions may be provided such that the two partitioncovers respectively support the shaft-support bearings. Hence, in thepresent application, the shaft-support portion having a shaft-supportbearing held by a specific partition cover is referred to as the firstshaft-support portion, and the shaft-support portion positioned on theopposite side of the rotor main body to the first shaft-support portionis referred to as the second shaft-support portion.

(3) In the embodiment described above, four locations on the statorinner diameter surface disposed in the circumferential direction D3serve as measurement and adjustment subjects, but there are nolimitations on the number of measurement and adjustment locations, andmeasurement and adjustment are possible as long as at least threemeasurement and adjustment locations are provided in the circumferentialdirection. As the number of measurement and adjustment locationsincreases, the axial center position of the stator S can be measured andadjusted gradually more accurately. Further, providing four locationshas the advantage of enabling direct measurement and adjustment ofcoordinates of the central axis position on orthogonal coordinates.

Furthermore, in the embodiment described above, the number ofmeasurement locations is equal to the number of adjustment locations,but these numbers may be different.

Further, as regards the phase in the circumferential direction D3, thephase of the stator inner diameter surface locations serving asmeasurement subjects and the phase of the stator inner diameter surfacelocations serving as adjustment subjects may match. In this case, inorder to perform stator core adjustment favorably, measurement ispreferably performed by maintaining the current axial position of theeccentric cam (the position in which the steel plate contacting theseating surface can be adjusted in the radial direction) and attaching adisplacement sensor to a location in the upper direction thereof. In sodoing, both measurement and adjustment can be performed favorably. Whenthis structure is employed, the adjustment amount can be derived easily.

Further, in the embodiment described above, five locations disposed atequal intervals in the axial direction D1 on the inner diameter surfaceof the stator S are set as measurement locations to be measured by thedisplacement sensors 20, but the number of measurement locations is notlimited thereto, and as long as at least two locations positioned on thetwo end sides of the stator S are set as measurement locations, theapproximate disposal state of the stator S along the axial direction D1can be measured. Note, however, that the disposal state of the stator Scan be measured more finely as the number of measurement locationsincreases.

(4) In the embodiment described above, an eddy current displacementsensor is used as a non-contact type displacement sensor that isselectively sensitive to a magnetic body or a conductor, but anothertype of displacement sensor, such as a magnetic displacement sensor thatdetects the distance to a magnetic body according to variation in themagnetic field in the vicinity of the magnetic body produced by magneticinduction, may be employed.

Any other type of sensor may also be employed, as long as the positionof the inner peripheral surface of the stator core can be detected.

(5) In the embodiment described above, the position of the stator innerdiameter surface is adjusted using the eccentric cam, but an adjustmentmechanism having a center in the axial center of the rotor, whichincludes an adjustment portion that can be widened or narrowed indiameter, may be used.

(6) In the embodiment described above, the displacement sensors aredisposed to measure positions on the inner diameter surface of thestator core, or in other words positions on the inner diameter side endsurface, i.e. the tip end surface of the teeth, but the displacementsensors may be disposed to measure positions on a different radialsurface such as the outer diameter surface of the stator core, and theposition of the stator core may be determined on the basis of the outputof the displacement sensors.

(7) In the embodiment described above, the disposal process fordisposing the measurement adjustment device 1 in the stator S isperformed after the temporary holding process for temporarily holdingthe stator S in the transmission case MC, but where appropriate, thissequence of processes may be reversed.

(8) In the embodiment described above, the cam 6 is disposed in aposition corresponding to the lower end portion of the stator core SC,or in other words a position in the vicinity of the position in whichthe stator core SC contacts the seating surface MC1, but the disposalposition of the cam 6 is not limited thereto. The cam 6 may be disposedin any position in which the position of the stator S can be adjustedappropriately, and in a preferred embodiment, the cam 6 is disposed soas to move a location of the stator S on the lower side of the center inthe vertical direction.

(9) In the embodiment described above, the position of the innerdiameter side end surface of the teeth t, i.e. the inner diametersurface of the stator in the fastened state fastened by the fasteningbolts, is measured by executing the measuring process, and the targetadjustment position of the stator in the open state is derived in theadjustment amount derivation process on the basis of the state ofdeformation on the inner diameter side end surface of the teeth in thefastened state, but when the state of deformation on the inner diametersurface of the stator S in the fastened state can be confirmed inadvance, the confirmation information obtained in the measuring processneed not be used.

(10) In the embodiment described above, the stator is fastened and fixedafter executing the adjustment process for adjusting the position of thestator in the open state, but it is possible to fasten the stator usingthe fastening bolts and adjust the fastening amount of the fasteningbolts relative to the stator on the basis of the state of deformation onthe inner diameter surface of the stator, determined in the measuringprocess, while executing the measuring process for measuring theposition of the inner diameter surface of the stator so that the stateof deformation of the inner diameter surface of the stator can be set inan appropriate state relative to the axial center of the rotor.

In this case, the fastening amount is adjusted such that therepresentative position of the stator matches the axial center of therotor within a predetermined allowable range.

The stator position measuring method and the stator position measuringdevice according to the present invention may be used effectively as astator position measuring method and a stator position measuring devicecapable of measuring the position of a stator core relative to the axialcenter of a rotor in a motor driving device provided in a hybridvehicle, for example, whereby stator positioning and adjustment can beperformed accurately and quickly.

According to an exemplary aspect of the invention, a measuring step andan adjusting step are performed first, whereupon the stator is fixed inthe stator fixing step and the rotor is shaft-supported on the motorcase in the rotor shaft-support step. Thus, manufacture of the motor iscomplete.

Here, the measuring step and adjusting step are performed in the rotornot-inserted state, in which the rotor is not inserted in the stator. Inother words, the position of the stator is measured and adjusted withonly the stator housed in the motor case using a space (the space inwhich the rotor is positioned when attached) formed in the interiorthereof.

The space for the rotor is large enough for inserting devices (measuringdevice and adjustment device) that measure and adjust the position ofthe stator, and the position of the stator can be measured and adjustedin the radial direction of the rotor using this space. As a result, theposition of the stator can be measured accurately in the measuring step,and the result thereof can be used to perform an adjustment.

Furthermore, measurement can be performed from the stator inner side,and adjustment can also be performed from the inside using themeasurement result. Therefore, the adjustment amount can be derivedeasily and accurately from the measurement result, and adjustment can beperformed accurately and quickly. In this case, the measuring step andadjusting step may be performed simultaneously or sequentially, and inso doing, a highly precise adjustment result can be obtained quickly andfavorably.

Having been adjusted to a favorable position in the manner describedabove, the stator is fixed to the motor case in the stator fixing step.In this step, the final position of the stator is determined, and theposition of a location on the inner diameter end of the stator shown inFIG. 3D is also determined.

The rotor is then shaft-supported on the motor case in the rotorshaft-support step. Thus, manufacture of the motor driving device iscomplete.

In the present application, a stator position measurement and adjustmentare performed from the inside of the stator during manufacture of themotor driving device, and therefore the position of the stator can beadjusted to a desired state relative to the rotor, in whichconcentricity between the rotor and stator can be secured, accuratelyand quickly. As a result, a motor driving device that generatessubstantially no vibration and so on can be manufactured.

The measuring step and the adjusting step are preferably executed in therotor not-inserted state by inserting a measurement adjustment deviceincluding the measuring device and adjustment device integrally in thestator.

By providing the measuring device and adjustment device integrally inthe measurement adjustment device, the positional relationshiptherebetween can be determined uniquely, and the measurement resultproduced by the measuring device can be used easily and quickly in theadjustment performed by the adjustment device.

Further, in the measurement adjustment device, positioning is performedusing the motor case or the axial center of the rotor (the axial centerof the rotor when the rotor is shaft-supported on the motor case), whichis determined in relation to the motor case, as a reference, and byproviding the measuring device and adjustment device integrally in themeasurement adjustment device, the position of the measuring device andadjustment device relative to this reference is determined uniquely. Asa result, the reliability of measurement and adjustment can beincreased, and manufacture can be performed accurately and quickly.

In the measuring step, the measuring device is preferably positionedusing a rotor shaft-support portion as a reference. The rotor isshaft-supported so as to be capable of rotating relative to the motorcase, and by positioning the measuring device using the rotorshaft-support portion as a reference, the position of the statorrelative to the axial center of the rotor with the rotor in ashaft-supported state can be determined accurately, and the motordriving device can be manufactured by determining the preferred positionof the stator from the measurement result. Hence, a motor driving devicein which the axial center of the rotor and the axial center of thestator are well-matched (adjusted to an appropriate positionalrelationship, as shown in FIG. 3D) can be obtained.

In the adjusting step, the adjustment device is preferably positionedusing the rotor shaft-support portion as a reference. The rotor isshaft-supported so as to be capable of rotating relative to the motorcase, and by positioning the adjustment device using the rotorshaft-support portion as a reference, the position of the statorrelative to the axial center of the rotor with the rotor in ashaft-supported state can be adjusted accurately, and thus manufactureof the motor driving device can be completed. Hence, a motor drivingdevice in which the axial center of the rotor and the axial center ofthe stator are well-matched (adjusted to an appropriate positionalrelationship, as shown in FIG. 3D) can be obtained.

According to an exemplary aspect of the invention, positioning of themeasuring device and adjustment device is performed using one or both ofthe first shaft-support portion and the second shaft-support portion,which serve as references when the motor driving device is assembled, asa reference. Hence, positioning can be performed using the shaft-supportportions for determining the rotary axis of the rotor, and therefore,concentricity between the stator and rotor can be aligned favorably inaccordance with a state in which the rotor is attached.

Here, when one of the first shaft-support portion and secondshaft-support portion is used as a reference, the operation can befacilitated by maintaining the motor case and the stator housed thereinin an attitude whereby the rotor is oriented in the vertical directionand centering can be performed comparatively easily using one of theshaft-support portions as a reference, for example.

On the other hand, when both shaft-support portions are used as areference, the pair of shaft-support portions actually used to supportthe rotor are used as references, and therefore strict concentricity canbe secured even when measurement and adjustment are performed in ahorizontal attitude, for example.

Here, “positioning using the shaft-support portion as a reference” is aconcept including both “a case in which positioning is performeddirectly from each shaft-support portion” and “a case in whichpositioning is performed from a reference position (the position ofpositioning device to be described below) for determining the positionof the shaft-support portion”.

According to an exemplary aspect of the invention, when the stator takesa laminated shape formed by laminating together steel plates, asdescribed above using FIG. 3 and so on, the stator is fastened to themotor case using a fastening device. By manufacturing the motor drivingdevice such that the position of the stator is measured and adjustedfrom the inside of the stator, as in the present application, problemssuch as deformation of the stator and the loss of concentricity betweenthe rotor axial center and stator axial center due to the fasteningoperation performed by the fastening device can be solved such that afavorable relationship between the two axial centers can be obtained ina motor driving device including a fastening device.

By executing the adjustment amount deriving step and the adjusting stepto adjust the position of the stator to the target adjustment position,and then fastening and fixing the stator using the fastening device, theposition of the stator in the fastened state can be set in anappropriate position relative to the axial center of the rotor.

In so doing, it is possible to envisage the stator in the fastenedstate, disposed in an appropriate position relative to the axial centerof the rotor, and derive the position of the stator in the open state asthe target adjustment position. Then, by fastening and fixing thestator, which has been positionally adjusted to the target adjustmentposition, using the fastening device, the state of deformation of theinner diameter surface, envisaged during derivation of the targetadjustment position, is reproduced, and thus the stator can be fixedeasily in an appropriate position relative to the axial center of therotor.

Before executing the adjustment amount deriving step, a measuring stepfor measuring the position of an inner diameter surface of the statorand determining the position of the stator relative to the axial centerof the rotor, which is used in the adjustment amount deriving step, fromthe measurement result is preferably executed with the stator in thefastened state.

In so doing, the position of the inner diameter surface of the statorstored in the motor case and fastened by the fastening device canactually be measured in the measuring step, and as a result, theposition of the stator in the fastened state relative to the axialcenter of the rotor can be determined accurately. Hence, in theadjustment amount deriving step, the accurate stator position can beused to derive the target adjustment position, and in the adjustingstep, the position of the stator can be adjusted to the targetadjustment position. Thus, the stator can be fixed in an appropriateposition relative to the axial center of the rotor.

According to an exemplary aspect of the invention, by deriving thetarget adjustment position in the manner described above, when thestator is fastened and fixed by the fastening device from the open stateafter being positionally adjusted to the target adjustment position, theaxial center of the inner diameter surface of the fixed stator and theaxial center of the rotor can be matched in the representative positionof the stator in the axial direction of the rotor. Hence, the stator canbe fixed in an appropriate position relative to the axial center of therotor such that the gap between the inner diameter surface of the fixedstator and the outer peripheral surface of the rotor is extremely evenin the axial direction of the rotor.

An average value of the position of the stator in a plurality oflocations in the axial direction of the rotor is preferably calculatedas the position of the axial center of the stator.

By calculating the position of the axial center of the stator, fromwhich the target adjustment position is derived, as an average value ofpositions in a plurality of locations on the stator in the axialdirection of the rotor, the position of the stator can be matched to theaxial center of the rotor, and hence the gap between the inner diametersurface of the fixed stator and the outer peripheral surface of therotor can be made more even in the axial direction of the rotor.

According to an exemplary aspect of the invention, the target adjustmentposition is set on the seating surface side of the stator, on which theload of the stator acts, and therefore, in the adjusting step, theposition of the stator can be adjusted on the seating surface side whilesuppressing tilting of the stator axial center.

According to an exemplary aspect of the invention, movement informationrelating to the movement direction and movement distance of the statorposition when the stator is switched from the open state to the fastenedstate can be determined from the position of the stator in the openstate and the position of the stator in the fastened state. Bydetermining the movement information in the adjustment amount derivingstep in this manner, a position offset by a corresponding distance in anopposite direction to the movement direction and movement distance ofthe movement information can be derived as the target adjustmentposition of the stator in the open state using an appropriate positionrelative to the rotor axial center as a reference. Hence, in theadjusting step, the position of the stator in the open state can beadjusted to the target adjustment position derived on the basis of themovement information in the manner described above such that when thestator is set in the fastened state, the position of the stator can befixed in an appropriate position relative to the axial center of therotor.

According to an exemplary aspect of the invention, when the stator isfastened by the fastening device, the stator fastening amount isadjusted on the basis of the position of the stator relative to theaxial center of the rotor, determined in the measuring step that isexecuted simultaneously. As described above, the position of the statorvaries according to the fastening amount. Therefore, by fastening thestator while executing the measuring step, fastening can be completedafter the stator has been positioned in an appropriate position, and inso doing, deformation of the stator accompanying fastening can beabsorbed by adjusting the fastening amount.

Thus, the position of the stator following fastening can be set in anappropriate state relative to the axial center of the rotor. Further, bysetting the position of the stator following fastening in an appropriatestate relative to the axial center of the rotor, fixing of the statorcan be completed without performing the subsequent adjusting step.

According to an exemplary aspect of the invention, by having thefastening device fasten the stator in a plurality of locations in theaxial direction of the rotor, deformation of the inner diameter surfaceof the stator due to fastening by the fastening device can besuppressed.

According to an exemplary aspect of the invention, when measuring theposition of the stator in the aforementioned rotor not-inserted state, anon-contact type displacement sensor that is selectively sensitive to amagnetic body or conductor forming the stator core is used, andtherefore the effects of substances other than the magnetic body orconductor interposed between the displacement sensor and stator core, inparticular varnish adhered to the radial surface of the stator core, canbe eliminated from the output of the displacement sensor. In otherwords, the displacement sensor is capable of measuring a position on theradial surface of the stator core relative to the axial center of therotor accurately, while positioned relative to the axial center of therotor, so as to exclude the effects of substances other than the statorcore, and therefore, the position of the stator can be determinedaccurately on the basis of the output of the displacement sensor.

Further, since the position of the stator relative to the axial centerof the rotor can be determined accurately in this manner, the positionof the stator relative to the axial center of the rotor to be insertedlater can be adjusted accurately and quickly. As a result, a motordriving device that generates little vibration and so on can beassembled with a high degree of precision.

Structurally, the stator takes a substantially cylindrical form. Hence,by measuring the positions of inner diameter surface locations on thestator at equal intervals in the circumferential direction and adjustingpositions on the inner diameter surface of the stator disposed at equalintervals in the circumferential direction of the rotor, the position ofthe center of the stator can be determined quickly, and an adjustmentcan be completed quickly, whereby manufacture of the motor drivingdevice can be completed.

According to an exemplary aspect of the invention, by setting the motorcase main body in a vertical attitude, an operation to house the statorin the motor case from the one end portion opening side and insert themeasuring device/adjustment device and so on into the stator can beperformed with favorable workability.

In the vertical attitude described above, the axial center of the rotorextends in a vertical direction, and therefore the measuring device oradjustment device can be supported between a horizontal or verticaldirection. As a result, the motor driving device can be manufacturedwhile supporting the measuring device and adjustment device in a stableand comparatively user-friendly state.

For example, when the measuring device or adjustment device is to bepositioned using the rotor shaft-support portions as a reference, asdescribed above, a sufficiently reliable axial center position can bedetermined even when only one of the rotor shaft-support portions isused, and hence workability is extremely favorable.

According to an exemplary aspect of the invention, even when the statortakes the laminated shape described above, such that relative movementoccurs between the plate-form bodies thereof, making it difficult tomaintain the linearity of the axial center of the stator, the stator canbe fixed in an appropriate position relative to the axial center of therotor.

When a motor driving device is obtained using the motor driving devicemanufacturing method described heretofore as a motor driving deviceincluding a motor case, a rotor which is shaft-supported from the motorcase and rotates in the interior thereof, and a stator disposedconcentrically with the rotor on the outer periphery of the rotor, amotor driving device that is highly reliable and generates littlevibration and so on in its final assembled state can be obtained.

1. A motor driving device manufacturing method for manufacturing a motordriving device comprising a motor case, a rotor, and a stator disposedconcentrically with the rotor on the outer periphery of the rotor,comprising a measuring step for measuring a position of the statorrelative to an axial center of the rotor from an inner side of thestator using a measuring device inserted in the stator; an adjustingstep for adjusting the position of the stator from the inner side of thestator based on a measurement result of the measuring step using anadjustment device inserted in the stator, wherein the measuring step andthe adjusting step are executed in a rotor not-inserted state, in whichthe stator is housed in the motor case and the rotor is not inserted inthe stator; a stator fixing step for fixing the stator in the motorcase; and a rotor shaft-support step for inserting the rotor in thestator and shaft-supporting the rotor on the motor case.
 2. The motordriving device manufacturing method according to claim 1, wherein themeasuring step and the adjusting step are executed in the rotornot-inserted state by inserting a measurement adjustment devicecomprising the measuring device and the adjustment device integrally inthe stator.
 3. The motor driving device manufacturing method accordingto claim 1, wherein, in the measuring step, the measuring device ispositioned using a rotor shaft-support portion as a reference.
 4. Themotor driving device manufacturing method according to claim 1, wherein,in the adjusting step, the adjustment device is positioned using a rotorshaft-support portion as a reference.
 5. The motor driving devicemanufacturing method according to claim 3, wherein: the motor casecomprises a motor case main body that is structured to house the statorand the rotor in an interior thereof, and a partition cover covering anopening in one end portion of the motor case main body in an axialdirection of the rotor, the rotor shaft-support portion includes a firstshaft-support portion provided on the partition cover and a secondshaft-support portion positioned on an opposite side of a rotor mainbody to the first shaft-support portion, in the measuring step and theadjusting step, the measuring device and the adjustment device arepositioned using one or both of the first shaft-support portion and thesecond shaft-support portion as the reference, and in the rotorshaft-support step, the rotor is shaft-supported on the firstshaft-support portion and the second shaft-support portion.
 6. The motordriving device manufacturing method according to claim 1, wherein: themotor driving device comprises a fastening device that fastens thestator to the motor case along an axis of the rotor, and in the statorfixing step, the stator is fastened and fixed by the fastening device.7. The motor driving device manufacturing method according to claim 6,wherein: in the measuring step, the position of the stator is measuredin a fastened state, in which the stator is fastened by the fasteningdevice, an adjustment amount deriving step for deriving a targetadjustment position of the stator in an open state, in which the statoris not fastened by the fastening device, is executed based on themeasurement result of the measuring step, in the adjusting step, theposition of the stator is adjusted to the target adjustment positionderived in the adjustment amount deriving step with the stator in theopen state, and after executing the adjusting step, the stator isfastened and fixed by the fastening device again.
 8. The motor drivingdevice manufacturing method according to claim 7, wherein, beforeexecuting the adjustment amount deriving step, a measuring step formeasuring the position of an inner diameter surface of the stator anddetermining the position of the stator relative to the axial center ofthe rotor, which is used in the adjustment amount deriving step, fromthe measurement result is executed with the stator in the fastenedstate.
 9. The motor driving device manufacturing method according toclaim 7, wherein, in the adjustment amount deriving step, a position ofthe stator when the axial center of an inner diameter surface of thestator and the axial center of the rotor match in a representativeposition of the stator in the axial direction of the rotor is derived asthe target adjustment position.
 10. The motor driving devicemanufacturing method according to claim 7, wherein an average value ofthe position of the stator in a plurality of locations in the axialdirection of the rotor is calculated as the position of the axial centerof the stator for deriving the target adjustment position.
 11. The motordriving device manufacturing method according to claim 7, wherein thetarget adjustment position is set on a seating surface side of thestator.
 12. The motor driving device manufacturing method according toclaim 7, wherein: in the adjustment amount deriving step, movementinformation of the position of the stator in the fastened state relativeto the position of the stator in the open state, in which the fasteningof the fastening device is released, is determined, and the targetadjustment position of the stator relative to the axial center of therotor is derived based on the movement information.
 13. A motor drivingdevice manufacturing method for manufacturing a motor driving devicecomprising a motor case, a rotor, a stator disposed concentrically withthe rotor on the outer periphery of the rotor, and a fastening devicefor fastening the stator to the motor case, comprising a measuring stepfor measuring a position of an inner diameter surface of the stator; anddetermining a position of the stator relative to an axial center of therotor from the measurement result, and at the same time, the stator isfastened by the fastening device, wherein based on the position of thestator measured in the measuring step, a fastening amount of thefastening device relative to the stator is adjusted.
 14. The motordriving device manufacturing method according to claim 6, wherein thefastening device fastens the stator in a plurality of locations in acircumferential direction of the rotor.
 15. The motor driving devicemanufacturing method according to claim 1, wherein the measuring deviceis a non-contact type displacement sensor that is selectively sensitiveto a magnetic body or conductor.
 16. The motor driving devicemanufacturing method according to claim 1, wherein: in the measuringstep, positions on an inner diameter surface of the stator disposed atequal intervals in a circumferential direction of the rotor aremeasured, and in the adjusting step, positions on the inner diametersurface of the stator disposed at equal intervals in the circumferentialdirection of the rotor are adjusted.
 17. The motor driving devicemanufacturing method according to claim 1, wherein: the motor casecomprises a motor case main body that is structured to house the statorand the rotor in an interior thereof, and a partition cover covering anopening in one end portion of the motor case main body in an axialdirection of the rotor, and each of the steps is executed in a state inwhich the motor case main body is held in a vertical attitude such thatan end portion opening is positioned on a vertically upper side.
 18. Themotor driving device manufacturing method according to claim 1, whereinthe stator takes a laminated shape formed by laminating a plurality ofplate-form bodies in the axial direction of the rotor.
 19. A motordriving device comprising the motor case, the rotors, and a statordisposed concentrically with the rotor on the outer periphery of therotor, wherein the motor driving device is manufactured using the motordriving device manufacturing method according to claim 1.